private bool OnTouchPressed(SKTouchEventArgs e)
{
var ticks = DateTime.Now.Ticks;
var location = e.Location;
initialTouch = location;
touches[e.Id] = new TouchEvent(e.Id, location, ticks, e.InContact);
// update the fling tracker
flingTracker.Clear();
// if we are in the middle of a multi-tap, then restart with more taps
if (multiTapTimer != null)
{
multiTapTimer.Dispose();
multiTapTimer = null;
tapCount++;
}
else
{
tapCount = 1;
}
var handled = false;
// start detecting once a finger is on the screen
var touchPoints = GetInContactTouchPoints();
if (touchPoints.Length > 0)
{
// try start a gesture
var args = new SKGestureEventArgs(touchPoints);
OnGestureStarted(args);
handled = args.Handled;
// if no gesture was detected, then we will handle it
if (!handled)
{
if (touchPoints.Length == 2)
{
previousValues = PinchValue.FromLocations(touchPoints);
touchMode = TouchMode.Multiple;
}
else
{
previousValues.Center = touchPoints.First();
touchMode = TouchMode.Single;
}
handled = true;
}
}
return(handled);
}
protected virtual void OnGestureEnded(SKGestureEventArgs e) => GestureEnded?.Invoke(this, e);
private bool OnTouchReleased(SKTouchEventArgs e)
{
var handled = false;
var ticks = DateTime.Now.Ticks;
var location = e.Location;
var releasedTouch = touches[e.Id];
touches.Remove(e.Id);
var points = GetInContactTouchPoints();
// no more fingers on the screen
if (points.Length == 0)
{
// check to see if it was a fling
var velocity = flingTracker.CalculateVelocity(e.Id, ticks);
if (Math.Abs(velocity.X * velocity.Y) > (flingVelocityThreshold * flingVelocityThreshold))
{
var args = new SKFlingDetectedEventArgs(velocity.X, velocity.Y);
OnFlingDetected(args);
handled = args.Handled;
}
// when tapping, the finger never goes to exactly the same location
var isAround = SKPoint.Distance(releasedTouch.Location, initialTouch) < touchSlopPixels;
if (isAround && (ticks - releasedTouch.Tick) < (e.DeviceType == SKTouchDeviceType.Mouse ? shortClickTicks : longTapTicks))
{
// add a timer to detect the type of tap (single or multi)
void TimerHandler(object state)
{
var l = (SKPoint)state;
if (!handled)
{
if (tapCount > 1)
{
var args = new SKTapDetectedEventArgs(location, tapCount);
OnDoubleTapDetected(args);
handled = args.Handled;
}
else
{
var args = new SKTapDetectedEventArgs(l);
OnSingleTapDetected(args);
handled = args.Handled;
}
}
tapCount = 1;
multiTapTimer?.Dispose();
multiTapTimer = null;
};
multiTapTimer = new Timer(TimerHandler, location, delayTapMilliseconds, -1);
}
else if (isAround && (ticks - releasedTouch.Tick) >= longTapTicks)
{
// if the finger was down for a long time, then it is a long tap
if (!handled)
{
var args = new SKTapDetectedEventArgs(location);
OnLongPressDetected(args);
handled = args.Handled;
}
}
}
// update the fling tracker
flingTracker.RemoveId(e.Id);
if (points.Length == 1)
{
// if there is still 1 finger on the screen, then try start a new gesture
var args = new SKGestureEventArgs(points);
OnGestureStarted(args);
handled = args.Handled;
// if no gesture was started, then we will handle it
if (!handled)
{
touchMode = TouchMode.Single;
previousValues.Center = points[0];
handled = true;
}
}
if (!handled)
{
// the gesture was not handled, so end it
var args = new SKGestureEventArgs(points);
OnGestureEnded(args);
handled = args.Handled;
if (points.Length == 0)
{
touchMode = TouchMode.None;
}
}
return(handled);
}